“Smart Cards” are known for use in the financial transactions, and typically have dimensions similar to credit cards. In some cases, the cards require physical contact with the pins of a reader to access information. In other cases, a passive RF link may be added so that the cards may be read via a reader. In most cases, these RF systems are short range, and require substantial proximity between the card and the reader for reading. In this cases, the user removes the card from the card from a purse or wallet and places it near the reader. Cards of this general types may be used for access control, purchase of goods in a store, in ATM machines, and for purchase of fuel.
Often when the transaction takes place, it may be awkward for the user to reach into his or her wallet or purse, and locate and remove the card to complete the transaction. Long wavelength communications protocols which allow transmission of information over greater distances, such as those described in ISO/IEC 18000-6, Type C, “Radio frequency identification for item management—Part 6.” (This standard, published by ISO in July 2006, is based on the EPC Gen 2 Class 1 UHF standard developed by EPCglobal.) could make it possible to read and write to a card without removing it from a wallet or purse and placing it in such close proximity to the reader. However, this approach has the disadvantage that the user does not have the ability to stop a transaction or to confirm that the transaction is correct before the communication with the card is completed. Indeed, it is not hard to envisage a person walking through a store unknowingly buying things with a card of this type.